Question

我使用示例以太网草图作为与Arduino软件捆绑在一起的Web客户端，而不更改除固件地址之外的东西，我将其更改为打印在以太网屏蔽背面的固件地址。

每当我将Arduino连接到我的网络并查看串行监视器时，我得到的唯一消息是“无法使用DHCP配置以太网”。

我已经设置了带有以太网屏蔽的Arduino Mega 2560，正确地将端口50连接到MISO，将51连接到MOSI，将52连接到SCK，将10连接到SS（在以太网板上打印时也称为ETHCS）。

你们有没有想过为什么会发生这种DHCP错误？

这是我的代码：

#include <SPI.h>
#include <Ethernet.h>

byte mac[] = {  0x90, 0xA2, 0xDA, 0x00, 0x73, 0xE4 }; //ethernet mac
IPAddress server(192, 168, 1, 9); //valid server IP in my network

EthernetClient client;

void setup() {
  Serial.begin(9600);

  if (Ethernet.begin(mac) == 0) {
    Serial.println("Failed to configure Ethernet using DHCP");

    for(;;)
      ;
  }

  delay(1000);
  Serial.println("connecting...");

  if (client.connect(server, 80)) {
    Serial.println("connected");

    client.println("GET /search?q=arduino HTTP/1.0");
    client.println();
  } 
  else {
    Serial.println("connection failed");
  }
}

void loop()
{
  if (client.available()) {
    char c = client.read();
    Serial.print(c);
  }


  if (!client.connected()) {
    Serial.println();
    Serial.println("disconnecting.");
    client.stop();

    for(;;)
      ;
  }
}

Answer 1

解决这个问题的解决方法是从插槽中取出Micro SD卡，我看到你的问题与故障有关，但其他有此问题的人应该在关闭Arduino后移除Micro SD卡。

Answer 2

试试这段代码:)它对我有用

#include <SPI.h>
#include <Ethernet.h>

// Enter a MAC address for your controller below.
// Newer Ethernet shields have a MAC address printed on a sticker on the shield
byte mac[] = {  
  0x00, 0xAA, 0xBB, 0xCC, 0xDE, 0x02 };

// Initialize the Ethernet client library
// with the IP address and port of the server 
// that you want to connect to (port 80 is default for HTTP):
EthernetClient client;

void setup() {
 // Open serial communications and wait for port to open:
  Serial.begin(9600);
  // this check is only needed on the Leonardo:


  // start the Ethernet connection:
  if (Ethernet.begin(mac) == 0) {
    Serial.println("Failed to configure Ethernet using DHCP");
    // no point in carrying on, so do nothing forevermore:
    for(;;)
      ;
  }
  // print your local IP address:
  Serial.print("My IP address: ");
  for (byte thisByte = 0; thisByte < 4; thisByte++) {
    // print the value of each byte of the IP address:
    Serial.print(Ethernet.localIP()[thisByte], DEC);
    Serial.print("."); 
  }
  Serial.println();
}

void loop() {

}

Answer 3

昨天我测试了那段代码。我的最后一个资源......如果DHCP失败，摆脱“无限”循环并返回静态IP。

Answer 4

你能尝试一下这段代码吗？

#if defined(ARDUINO) && ARDUINO > 18
#include <SPI.h>
#endif
#include <Ethernet.h>
#include <EthernetDHCP.h>

// MAC Address
byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };

const char* ip_to_str(const uint8_t*);

// Initialize the Ethernet server library
Server server(8080);

void setup()
{
  Serial.begin(9600);

  Serial.println("Attempting to obtain a DHCP lease...");

  // Initiate a DHCP session. The argument is the MAC (hardware) address that
  // you want your Ethernet shield to use. This call will block until a DHCP
  // lease has been obtained. The request will be periodically resent until
  // a lease is granted, but if there is no DHCP server on the network or if
  // the server fails to respond, this call will block forever.
  // Thus, you can alternatively use polling mode to check whether a DHCP
  // lease has been obtained, so that you can react if the server does not
  // respond (see the PollingDHCP example).
  EthernetDHCP.begin(mac);

  // Since we're here, it means that we now have a DHCP lease, so we print
  // out some information.
  const byte* ipAddr = EthernetDHCP.ipAddress();
  const byte* gatewayAddr = EthernetDHCP.gatewayIpAddress();
  const byte* dnsAddr = EthernetDHCP.dnsIpAddress();

  Serial.println("A DHCP lease has been obtained.");

  Serial.print("My IP address is ");
  Serial.println(ip_to_str(ipAddr));

  Serial.print("Gateway IP address is ");
  Serial.println(ip_to_str(gatewayAddr));

  Serial.print("DNS IP address is ");
  Serial.println(ip_to_str(dnsAddr));

  // Start the server
   server.begin();
}

void loop()
{
  // You should periodically call this method in your loop(): It will allow
  // the DHCP library to maintain your DHCP lease, which means that it will
  // periodically renew the lease and rebind if the lease cannot be renewed.
  // Thus, unless you call this somewhere in your loop, your DHCP lease might
  // expire, which you probably do not want :-)
  EthernetDHCP.maintain();

  // listen for incoming clients
  Client client = server.available();
  if (client) {
    // an http request ends with a blank line
    boolean currentLineIsBlank = true;
    while (client.connected()) {
      if (client.available()) {
        char c = client.read();
        // if you've gotten to the end of the line (received a newline
        // character) and the line is blank, the http request has ended,
        // so you can send a reply
        if (c == '\n' && currentLineIsBlank) {
          // send a standard http response header
          client.println("HTTP/1.1 200 OK");
          client.println("Content-Type: text/html");
          client.println();

          // Some misc. HTML 
          client.println("<title>Arduino Control Panel</title>");
          client.println("<center><h1>Control Panel</h1></center>");
          client.println("<p></p>");

          // output the value of each analog input pin
          for (int analogChannel = 0; analogChannel < 6; analogChannel++) {
            client.print("Analog input ");
            client.print(analogChannel);
            client.print(" is ");
            client.print(analogRead(analogChannel));
            client.println("<br />");
          }
          break;
        }
        if (c == '\n') {
          // you're starting a new line
          currentLineIsBlank = true;
        } 
        else if (c != '\r') {
          // you've gotten a character on the current line
          currentLineIsBlank = false;
        }
      }
    }
    // give the web browser time to receive the data
    delay(1);
    // close the connection:
    client.stop();
  }
}

// Just a utility function to nicely format an IP address.
const char* ip_to_str(const uint8_t* ipAddr)
{
  static char buf[16];
  sprintf(buf, "%d.%d.%d.%d\0", ipAddr[0], ipAddr[1], ipAddr[2], ipAddr[3]);
  return buf;
}

Answer 5

我有同样的问题。

我发现它使用某些类型的开关产生的问题因为我有两个（Encore Model ENH908-NWY Ver 3和其他IntelliNet Model 523301 Rev1）。

使用交换机Encore，DHCP出现问题，Ethernet.begin（mac）返回0，但使用IntelliNet进程DHCP工作没有问题。

我家里有一台ADSL华为处理DHCP请求。

我认为它用以太网屏蔽r3解决的问题，但我没有尝试过。

我用它发布代码我尝试了DHCP请求。

当我尝试以太网盾r3时，我来这里告诉你。

问候！

属性mac通常被定义为具有六个Hex的数组字节。

void networkSetting(){
    byte stateNet = 0;

    //Se realiza petición DHCP para otros parámetros de Red si no están en memoria ya sea por System o Usuario
    if ((EEPROM.read(userConfig) != setted) && (EEPROM.read(systemConf) != setted)) {
        //Configurar el Socket solo con Mac
        if (Ethernet.begin(mac) == 0){
            Serial.println("DHCP not initialized! Try again...");
            return;
        }

        //Verificamos conexión
        stateNet = Ethernet.maintain();

        //Ponemos bandera de parámetros de Red System seteados si cumple alguna condición
        if (stateNet == 0 || stateNet == 2 || stateNet == 4)
        {
            //Obtenemos parámetros de Red
            getNetParams();
            //Guardamos parámetros de Red
            saveNetParams();
            //Seteamos configuración por Sistema
            EEPROM.write(systemConf, setted);
        } else {
            //Resetear Bandera de parámetros de System (Tomará DHCP en el próximo Reinicio)
            EEPROM.write(systemConf, 0);
        }
    } else {
        //cargar parámetros de red
        loadNetParams();

        //Configurar el Socket con los parámetros desde la memoria  
        Ethernet.begin(mac, ip, gateway, gateway, subnet);
    }

    //Iniciar el Servidor
    server.begin();

    //Se envían datos de estado de Red y Port a Puerto Serial
    Serial.println("Running as " + String(stateNet) + " in port " + String(port) + "!");
}

我附上两个案件的抓拍。

The bad test with switch Encore

The good test with switch IntelliNet

Answer 6

无法使用DHCP配置以太网。 Ethernet.begin（mac）始终返回0。

许多人报告完全相同的问题。看来您必须连接到路由器，而不是交换机。

如果不是，则必须将PC用作服务器请点击此链接以了解更多信息-> https://www.youtube.com/watch?v=4xwwV_s9Gik

Arduino DHCP无法配置

6 个答案: